[Devel] [PATCH net-2.6.26 2/3][TUN][NETNS]: Actually make the tun_dev_list per-net.

[Pavel Emelyanov]

Remove the static tun_dev_list and replace its occurrences in
driver with per-net one.

It is used in two places - in tun_set_iff and tun_cleanup. In 
the first case it's legal to use current net_ns. In the cleanup
call - move the loop, that unregisters all devices in net exit
hook.

Signed-off-by: Pavel Emelyanov <xemul at openvz.org>

---
 drivers/net/tun.c |   35 +++++++++++++++++------------------
 1 files changed, 17 insertions(+), 18 deletions(-)

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 3d518b1..e3210bf 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -62,6 +62,7 @@
 #include <linux/if_ether.h>
 #include <linux/if_tun.h>
 #include <linux/crc32.h>
+#include <linux/nsproxy.h>
 #include <net/net_namespace.h>
 
 #include <asm/system.h>
@@ -76,7 +77,6 @@ struct tun_net {
 	struct list_head dev_list;
 };
 
-static LIST_HEAD(tun_dev_list);
 static const struct ethtool_ops tun_ethtool_ops;
 
 /* Net device open. */
@@ -440,12 +440,12 @@ static void tun_setup(struct net_device *dev)
 	dev->destructor = free_netdev;
 }
 
-static struct tun_struct *tun_get_by_name(const char *name)
+static struct tun_struct *tun_get_by_name(struct net *net, const char *name)
 {
 	struct tun_struct *tun;
 
 	ASSERT_RTNL();
-	list_for_each_entry(tun, &tun_dev_list, list) {
+	list_for_each_entry(tun, &net->tun->dev_list, list) {
 		if (!strncmp(tun->dev->name, name, IFNAMSIZ))
 		    return tun;
 	}
@@ -453,13 +453,13 @@ static struct tun_struct *tun_get_by_name(const char *name)
 	return NULL;
 }
 
-static int tun_set_iff(struct file *file, struct ifreq *ifr)
+static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
 {
 	struct tun_struct *tun;
 	struct net_device *dev;
 	int err;
 
-	tun = tun_get_by_name(ifr->ifr_name);
+	tun = tun_get_by_name(net, ifr->ifr_name);
 	if (tun) {
 		if (tun->attached)
 			return -EBUSY;
@@ -472,7 +472,7 @@ static int tun_set_iff(struct file *file, struct ifreq *ifr)
 		     !capable(CAP_NET_ADMIN))
 			return -EPERM;
 	}
-	else if (__dev_get_by_name(&init_net, ifr->ifr_name))
+	else if (__dev_get_by_name(net, ifr->ifr_name))
 		return -EINVAL;
 	else {
 		char *name;
@@ -525,7 +525,7 @@ static int tun_set_iff(struct file *file, struct ifreq *ifr)
 		if (err < 0)
 			goto err_free_dev;
 
-		list_add(&tun->list, &tun_dev_list);
+		list_add(&tun->list, &net->tun->dev_list);
 	}
 
 	DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
@@ -570,7 +570,7 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file,
 		ifr.ifr_name[IFNAMSIZ-1] = '\0';
 
 		rtnl_lock();
-		err = tun_set_iff(file, &ifr);
+		err = tun_set_iff(current->nsproxy->net_ns, file, &ifr);
 		rtnl_unlock();
 
 		if (err)
@@ -805,6 +805,15 @@ static int tun_init_net(struct net *net)
 
 static void tun_exit_net(struct net *net)
 {
+	struct tun_struct *tun, *nxt;
+
+	rtnl_lock();
+	list_for_each_entry_safe(tun, nxt, &net->tun->dev_list, list) {
+		DBG(KERN_INFO "%s cleaned up\n", tun->dev->name);
+		unregister_netdevice(tun->dev);
+	}
+	rtnl_unlock();
+
 	kfree(net->tun);
 	net->tun = NULL;
 }
@@ -928,17 +937,7 @@ err_pernet:
 
 static void tun_cleanup(void)
 {
-	struct tun_struct *tun, *nxt;
-
 	misc_deregister(&tun_miscdev);
-
-	rtnl_lock();
-	list_for_each_entry_safe(tun, nxt, &tun_dev_list, list) {
-		DBG(KERN_INFO "%s cleaned up\n", tun->dev->name);
-		unregister_netdevice(tun->dev);
-	}
-	rtnl_unlock();
-
 	unregister_pernet_device(&tun_net_ops);
 }
 
-- 
1.5.3.4